Explosion-proof operating mechanism for running sign



July 23, 1957 J. H. DOININELLY EIAL 2,799,954

EXPLOSION-PROOF OPERATING MECHANISM FOR RUNNING SIGN Filed Feb. 24, 1951 4 ets-Sheet 1 INVENTORS'.

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J. H. DONNELLY ETAL 2,799,954

July 23, 1957 EXPLOSION-PROOF OPERATING MECHANISM FOR RUNNING SIGN Filed Feb. 24, 1951 4 Sheets-Sheet 2 s l & H k5 it. 1%! 1 PM. R e N u I: s a. a; 5 s m #0 WM t v 1.. I! MIN/1...: m -r n l 1 l l I 1 I I 3 r V w 4 W T W Q N H v A @Qv g. 1 F v 4 w W II I N \V mwl as w 9w k 1 fi w liwlli UC/ ll: w Y W \l I MU Rfldh hn g @I/ B H n g a Q I x k a N. E n m wl y 1957 J. H. DONNELLY ET AL 2,799,954

EXPLOSION-FROG} OPERATING MECHANISM FOR RUNNING SIGN 4 sheets-911999 5 Filed Feb. 24. 1951 y s T 4 N p S fl I J M W mz BY a,

N w Wu ks w J y 1957 J. H. DONNELLY EI'AL 2,799,954

EXPLOSION-PROOF OPERATING MECHANISM FOR RUNNING SIGN F iled Feb. 24, 1951 4 Sheets-Sheet 4 INVENTOR.

Lou is Biro United States Patent 9 EXPLOSION-PROOF OPERATING MECHANISM FOR RUNNING SIGN John H. Donneliy and Louis Biro, New York, N. Y. Application February 24, 1951, Serial No. 212,626

Claims. (31. 40-32 The present invention relates to an explosion-proof, motor-operated mechanism for a flashing or running sign. More particularly it relates to such mechanism and running sign adapted for use in an environment where there is present the hazard of explosion of combustible gases by electric sparks, for example, at the top of a gasolene dispensing pump, in coal mines and the like.

For advertising purposes, the provision of a running sign atop a gasolene dispensing pump is very desirous but, owing to the possibility of gasolene vapors gaining access to the motor housing and the hazard of explosion of such vapors by an electric spark from the motor, such running signs, so far as we are aware, have never been considered feasible. By the same token, the use of illuminated flashing warning slogans in coal mines and other places where explosive gas and dust mixtures are frequently found has also not been considered feasible.

The primary object of our invention is to provide an electrically operated illuminated flashing or running sign capable of use at locations whereat explosive gas mixtures may be present.

A further object is to provide such illuminated running sign in which the intelligence conveyed by the sign may be readily changed without exposing the electrical connections or the spark-producing operating parts of the motor to an explosive mixture which may be present in the environment of the sign.

A still further object is to provide an electrically operated, explosion-proof motor of novel design.

A still further object is to provide an electrically operated, explosion-proof motor and running sign of simple, sturdy, compact and practicable construction, reasonable in manufacturing cost and capable of performing its intended function in an efficient and trouble-free manner.

With the foegoing and other objects in view, our invention comprises the construction, combinations and arrangements of parts set forth in the following detailed description and illustrated in the accompanying drawings, wherein:

Figure 1 is a perspective view of a gasolene dispensing pump to which our invention has been applied.

Fig. 2 is a view in top plan of the device embodying our invention, with parts broken away and with the enclosing hood removed.

Fig. 3 is a view partly in front elevation and partly in section of the device embodying our invention, the front portion of the enclosing hood being cut away and the sign tape being omitted.

Fig. 4 is a view partly in end elevation and partly in section of the device embodying our invention on a somewhat larger scale than shown in Fig. 3, the end portion of the enclosing hood being cut away and the sign tape being omitted.

In the drawings wherein like reference characters denote corresponding parts through the several views, the reference numeral designates a conventional gasolene dispensing pump housing having a decorative canopy 11 Which is surmounted by a dome-shaped member 12 hav- "ice ing sight openings 13 in opposite faces thereof, through which an illuminated flashing or running sign 14 is visible. The invention hereinafter described and claimed is directed to the flashing or running sign housed within the dome 12 and to the explosion-proof motor mechanism for operating the sign. v

The pump housing 10 has an inner cap 15 having a central opening 16 and the decorative canopy 11 has a top 17 formed with a central opening 18, through which openings 16 and 18 projects a portion of an explosionproof housing 19 within which are mounted a synch'I nous induction motor consisting of a stator 20 and a rotor 21 and additional electrical means and connections, which will be presently described.

The explosion-proof housing 19 is preferably of sturdy metallic construction and, as shown in Figs. 3, 4 and 5, has a lateral extension 22, a substantially central depending lug 23, a substantially central upwardly-extending lug 24, front and rear projecting lugs 25 and 26, and a removable, screw-threaded cover plate 27. The lateral extension 22 is cored out, as indicated at 28 and 29, and mounted within said cored out portions is a shaft 3%), one end of which is supported in a bearing 31 mounted in the extreme left end of the extension, and the other end of said shaft is carried by the rotor 21 of the motor. Fixedly mounted on the shaft 30 and disposed within the cored out portion 29 is a worm 32 through which rotation of the rotor is transferred to a worm wheel 33 which drives the running sign, as will be presently described. The cored out portion 'whereat it communicates with the interior of the housing 19 is slightly enlarged, as shown at 34, and mounted in said enlargement is a bearing 35 for the shaft 30, the fit between the shaft and said bearing being such as to provide a restricted flame path between the cored out portion 28 and the interior of the housing, that is to say, the clearance between the shaft and the bearing is such as to preclude the passage of combustible gases or flame from the environment exterior of the housing to the interior of the hon-sing through the bearing 35. The stator 20 and the rotor 21 are wholly supported from the left end wall of the housing by a U-shaped bracket 36, studs 37, spacer bushings 38 and nuts 39. For supplying electric current to the motor within the housing a pair of wires 40 extend upwardly through a slip-joint connector 41 which is threaded into a tapped opening 42 in the central depending lug 23. In order not to twist the wires in making the aforementioned connections, the wires are first drawn through the slip-joint connector and held in spaced relation therein by a perforated insulating washer 43, after which the upper interior portion of the slip joint connector is filled with a sealing compound 44 which precludes the entrance therethrough of combustible gases to the interior of the housing 19. A packing gasket 4-5 provides a tight seal between the slip-joint connector 41 and the tapped opening 42. After the slipjoint connector is secured in place, the ends of the wires within the housing are connected to a suitable three-way switch 46 which is operable by a plunger 47 extending through an orifice in the right end wall of the housing, which orifice provides with the plunger a restricted flame pitch. Also mounted within the housing and controlled by the three-way switch are wires leading outwardly from the housing to a pair of fluorescent tubes 48 and to a ballast 49 for the fluorescent tube. The electrical connections between the switch, the stator of the motor, the fluorescent tubes and the ballast are not shown for the sake of simplicity. The ballast 49 is mounted on suitable brackets 50 supported within the housing. The wires 40 are connected to a source of current supply in a conduit box 51 mounted within the pump housing 13 and the slip=joint connector 41 is connected to said conduit box by a slip-joint connector 52 which screwthreadedly engages a tapped. opening 53 in said conduit box.

*Thefluorescent tubes'48 are 'fountedflin sockets 54 which are supported by flat lugs 55 formed on elbows 56, which,jin turn, are rigidly connected through conduit nipples 57 with the interior of the housing 19, into tapped holes 58 in the lugs 25 and 26 of which the conduits are threaded. The sqrew-threaded connections between the conduit nipples 57 and the tapped holes 58 and the elbows 56 are sealed with an appropriate sealing compositionto prevent the entrance of explosive gas into the conduits and thence into the housing. Suitable brackets of insulating material 59are' interposed between the nipples andthe sockets 54. To provide a suitable reflecting surface for the fluorescent tubes concave reflectors 60 are provided, which reflectors are conveniently secured to the outer wall of the lugs 25 and 26 by screws 61.1 a a The flashing or running sign which is operated by the motor within the housing through the shaft 39, Worm 32 and worm wheel 33' consists of an endless web 62 containing intelligence in the form of characters formed by perforations in the web, said web being trained over a plurality of spaced apart rollers 63, 64 and 65 to define the path of movement of the web. The rollers 63 are idler rollers each rotatably supported in a U-shaped bracket66 secured to a flat lug 55 of an elbow 56. The roller 64 is' a spring-tensioned take-up roller and the roller 65 is'the drive roller. For reinforcing the support of the U-shaped brackets 66 and for more sturdily supporting the explosion-proof housing 19 and the flashing sign mechanism into a single unit or chassis, a pair of roller supporting brackets 66 at each end of the device are connected to an angle bar 67. The angle bar 67 may,

in turn, beemployed for securingthe chassis to the cap and canopy top 17 when mounting the device on a gasolene dispensing pump. a Any securing means such as an anglebar bracket 68 and screws 69 may be used for securing the chassis to the pump housing. In addition to or in lieu of the securing means 68, 69, the chassis may be secured to the pump housing by angle brackets 70 mounted on thefaces of lugs 25, 26, by screws 71 and fastened to the canopies 15 and 17 by screwsr72.

'The idler rollers 63 are mounted for free rotation in any desired manner and, as herein shown (Fig. 4), are supported between a pair of set-screws 73 screw-threaded in thearms of brackets 66, the inner ends of said screws being cone-shaped and engage anti-friction bearings 74 mounted in the rollers. The tension takeup roller 64 hasfixedly mounted in each end'thereof a screw-threaded stud75,'the-free end of which engages 'in an opening 76 in a U-shaped slide 77.which is freely movable and has lateral play alongside rails 78 formed on the arms 79 of a U-shaped bracket8tl. The openings 76 in the slides 77 are of slightly larger diameter than the ends of the screw-threadedmember 75 so that the latter may'have play in said openings. The slides 77 are normally biased toward the free ends of thearms 79 by tension springs 81, one end of each spring being secured to a slide 77 and the other end of which is secured to a bent tang 82 formed at the free' end of each arm 79. The U-shaped bracket 80 is formed of light metal and its lower 'arm is rigidly fastened to an arm of the bracket 67, the upper arm of said U-shaped bracket being free and adapted for limited relative movement to its lower arm. By virtue of the construction of the mounting of the tension takeup roller 64 it will be apparent that it has limited canting movement in all directions about its axis and hence serves'to insure true running of the endless web 62 in the event of any lack of alignment of the rollers 63 and 65 arising from constructional or mounting inequalities. The roller 65 is mounted for free rotation upon .a shaft 84, the lower end of which is fixed in the lateral extension 22 of the housing, and said roller 'is driven by the worm wheel 33 which is loosely mounted on the shaft 84. The driving connection between the worm wheel and the roller 65 may be of any desired construction. A cover plate having an opening therein through which the shaft 7 84 extends, is mounted over the extension 22. The drive roller is preferably formed with a peripheral surface 85 which is suitably roughened to increase its frictional engagement with the endless web 62. As herein shown, the

drive roller is formed with a central bushing 86 which projects above the roller and encircles the shaft 84, said bushing being adapted for frictional engagement with an extension shaft. (not shown) adapted to project through the top of the dome-shaped member 12 through an opening therein 87, which opening is normally closed by a removable closure cap 88 of any preferred construction. A similar closure cap 89 may be provided in the domeshaped member 12 in axial alignment with the central,

' upwardly projecting lug 24, which latter may be drilled through and be provided with a closure plug 90. The removable closure cap 89-and the removable plug 90 arefprimarily provided should it be desired to mount on the top of the dome 12 any supplemental illuminating means, the wires to which will then be extended through the opening in the lug 24 in a manner analogous to that in'which the wires 40 are extended through the projection 23 to preclude the entrance of combustible gases into'the housing 19.

The dome-shaped member 12 is of a size and shape to fit; over and completely enclose the explosion-proof motor housing and the running sign mechanism and is formed at its lower edge with an inturned flange 91 adapted to seat on a packing gasket 92 disposed Within a channel 93 formed in the decorative canopy 11. Any suitable means may be employed for holding the dome in tight engagement with the top of the decorative canopy. The sight openings 13 in the dome are formed by cutting away part of the material thereof and forming inwardly directed flanges 94 at the edges defining the cut-out, which flanges engage in moulded rubber frames 95, which are recessed to accommodate and hold glass or other lighttransmitting panels 96. The rubber frames, with the glass panels therein, are held firmly in place by metal frames 97' having sight openings 98 therein of slightly larger area than that defined by the rubber moulded frames 95, the said metal frames 97 being secured to'the inner faces of the dome-shaped member 12 by nuts 99 engaging threaded studs 100 welded to said inner faces and extending through openings in brackets 101 carried by the frame.

From an inspection of Fig. 2 of the drawings it will be seen that the endless Web 62 which is trained and travels over the rollers 63, 64 and 65 passes between the fluorescenttubes 48 and the rear of the metal frames 97 and, as the intelligence contained on the web passes the registering sight openings 98 and 13, the intelligence conveyed by the sign becomes visible from the exterior of the pump housing. Where such running sign is mounted atop a gasolene dispensing pump or the like it will be apparent from the construction of the device as hereinbefore described that it will be impossible for'any of the combustible gasolene vapors which may be present within the pump housing or surround'mg the same to gain access into the interior of the'housing 19 and there be ignited or exploded by any sparks which may be created therein by the operation of the control switch for the motor and illuminating means for the sign. And, should alimited quantity of such vapors gain entrance within the housing, any explosion thereof will be confined within the housing. It will furthermore be appreciated that the motor housing and the running sign mechanism may be assembled as a unit and readily applied to the top or canopy of a dispensing pump housing; Also, that where it is desired to change the sign, this may be readily accomplished by removing the dome-shaped member 12 and roller 64 operating to facilitate such removal and change of the webs.

While our invention has been described herein as applicable to a gasolene dispensing pump housing, it will be apparent that its utility is not so limited and that it is equally applicable to any environment where explosive gas mixtures may be present and the danger of explosion due to electric spark may exist.

While we have shown and described one embodiment of our invention, it is to be understood that changes in constructional and operational details may be made therein within the range of engineering and mechanical skill without departing from the spirit of the invention as hereinafter claimed.

What we claim is:

1. In combination, an electrically operated motor for use in an evironment of explosive gas mixtures and an illuminated running sign exteriorly of and operable by said motor, comprising a sturdy metallic housing completely enclosing therein a rotor and a stator constituting the motor, the rotor having a shaft extending outwardly of the housing through an orifice in one wall thereof, which orifice provides with the shaft a restricted flame path, said running sign including a movable member containing intelligence, driving means operated by the motor shaft for operating the movable member, electrical illuminating means for the movable member, a control switch within the housing for the motor and wholly enclosed electrical connectors leading from the switch to the motor and to the illuminating means, electric current conducting wires extending through the housing to the control switch and a plunger means for operating said control switch extending outwardly of the housing through an orifice therein which provides with the plunger a restricted flame path.

2. The combination according to claim 1 wherein the illuminating means are fluorescent tubes requiring a starter ballast and a starter ballast mounted within the housing and controlled by the plunger operable switch.

3. In combination, an electrically operated motor for use in an environment of explosive gas mixtures and an illuminating running sign exteriorly of and operable by said motor, comprising a sturdy metallic housing completely enclosing therein a stator and a rotor constituting the motor, the housing having an orifice in one wall thereof, the rotor having a shaft extending outwardly through said orifice and providing therewith a restricted flame path, said running sign including a movable, endless web containing intelligence trained over a plurality of spaced apart rollers disposed to define the path of movement of the web, one of said rollers being the driving roller for the Web, means for rotating the driving roller from the extending end of the rotor shaft, the rollers being rotatably supported by means rigidly connected to the housing, fixedly mounted illuminating means disposed rearwardly of the movable, endless web and supported by the same means which support the non-driving rollers, said supporting means including a rigid conduit and elbow fittings through which current-carrying wires extend from the interior of the housing to said illuminating means, said elbow fittings having lugs, and the non-driving rollers being mounted in brackets which are fixedly secured to said lugs.

4. In combination, an electrically operated motor for use in an environment of explosive gas mixtures and an illuminating running sign exteriorly of and operable by said motor, comprising a sturdy metallic housing completely enclosing therein a stator and a rotor constituting the motor, the housing having an orifice in one Wall thereof, the rotor having a shaft extending outwardly through said orifice and providing therewith a restricted flame path, said running sign including a movable, endless web containing intelligence trained over a plurality of spaced apart rollers disposed to define the path of movement of the web, one of said rollers being the driving roller for the web, means for rotating the driving roller from the extending end of the rotor shaft, the rollers being rotatably supported by means rigidly connected to the housing, the housing, the running sign and the means rigidly connecting the running sign to the housing constituting a unitary chassis, means on said chassis for rigidly mounting the unit to a supporting structure and a hood mounted on the supporting structure enclosing the chassis, said hood having a side opening through which the flashing sign is rendered visible through the hood.

5. A flashing sign comprising an endless web containing intelligence, a plurality of rollers over which said web is movable, one of said rollers being a driving roller and another of said rollers being a take-up roller, spring means acting on said take-up roller for biasing it in a direction to tension the web, and said take-up roller being mounted by a shaft capable of limited radial movement, the ends of said shaft being mounted in bearings having a slightly larger diameter than the shaft ends whereby to permit limited tilting of the roller and true running of the web, the spring biased take-up roller being mounted in slides, which, in turn, are mounted on the arms of a U-shaped bracket, one arm of which is fixedly anchored and the other arm of which is free and capable of lateral movement relatively to the firmly anchored arm.

References Cited in the file of this patent (Addition to No. 391,676 of Sept. 3, 1908) 

